Buggy code:
abstract class Node implements Iterable < Node > { Segment2D bisector ; private boolean isProcessed = false ; boolean isReflex ; protected Node next ; private Node previous ; protected OriginalEdgeStart currentEdgeStart ; protected OriginalEdgeStart previousEdgeStart ; protected Segment2D currentEdge ; final Point2D vertex ; Node ( Point2D point , OriginalEdgeStart previousEdgeStart , OriginalEdgeStart currentEdgeStart ) { } void growAdjacentFaces ( Node newNode ) { } void growRightFace ( Node newNode ) { } void growLeftFace ( Node newNode ) { } private void growFace ( Node newNode , OriginalEdgeStart faceStart ) { } protected Node ( Point2D vertex ) { } public void drawLav ( ) { } abstract boolean hasPair ( ) { } SplitNode getPair ( ) { } Node next ( ) { } Node previous ( ) { } Segment2D previousEdge ( ) { } public Segment2D currentEdge ( ) { } void setProcessed ( ) { } public boolean isProcessed ( ) { } public void computeReflexAndBisector ( ) { } private boolean isReflex ( Point2D a1 , Point2D a2 , Point2D b1 , Point2D b2 ) { } public void setPreviousInLav ( Node previous ) { } public boolean isInLavOf2Nodes ( ) { } @ Override public Iterator < Node > iterator ( ) { if ( isProcessed ) { assert false ; } return new Iterator < Node > ( ) { List < Point2D > points = new ArrayList < > ( 100 ) ; Node start = Node . this ; Node node = Node . this . previous ; int i = 0 ; @ Override public boolean hasNext ( ) { return ( ( node . next ) != ( start ) ) || ( ( i ) == 0 ) ; } @ Override public Node next ( ) { node = node . next ; if ( node . isProcessed ( ) ) { showCurrentLav ( ) ; throw new RuntimeException ( "Node<seq2seq4repair_space>not<seq2seq4repair_space>in<seq2seq4repair_space>lav" ) ; } checkLavCorrectness ( ) ; points . add ( node . vertex ) ; return node ; } private void showCurrentLav ( ) { Node current = start ; do { canvas . draw ( new Segment2D ( current . vertex , current . next . vertex ) , DrawingSegment2D . withColorDirected ( Color . cyan , 0.5 ) ) ; current = current . next ; } while ( current != ( node ) ) ; assert Boolean . TRUE ; } private void checkLavCorrectness ( ) { <START_BUG> if ( ( ++ ( i ) ) > 100 ) { <END_BUG> drawLav ( ) ; throw new RuntimeException ( "Too<seq2seq4repair_space>many<seq2seq4repair_space>iterations" ) ; } } private void drawLav ( ) { Iterator < Color > colors = Iterators . cycle ( Color . darkGray , Color . gray , Color . lightGray , Color . white ) ; for ( int i = 0 ; i < ( ( points . size ( ) ) - 1 ) ; i ++ ) { canvas . draw ( new Segment2D ( points . get ( i ) , points . get ( ( i + 1 ) ) ) , DrawingSegment2D . withColorThin ( colors . next ( ) ) ) ; } canvas . draw ( start . vertex , DrawingPoint2D . withColorAndSize ( Color . yellow , 2 ) ) ; } } ; } public boolean isPair ( Node node ) { } @ Nullable protected SkeletonEvent computeNearerBisectorsIntersection ( ) { } private boolean splitPointIsBetterThanShrinkPoint ( @ Nullable SkeletonEvent splitEvent , @ Nullable Point2D shrinkPoint ) { } private RayIntersection bisectorsIntersection ( Node node ) { } @ Nullable private static EdgeEvent trySameLineIntersection ( RayIntersection intersection , Node current , Node target ) { } @ Nullable private SplitEvent findSplitEvent ( ) { } private Point2D computeSplitPoint ( Segment2D oppositeEdge ) { } private boolean nodeIsAppropriate ( Node node ) { } private boolean newSplitPointIsBetter ( Point2D oldSplitPoint , Point2D newSplitPoint ) { } private boolean nodeIsNeighbor ( Node node ) { } private boolean currentEdgeIntersectsInFrontOfOppositeEdge ( Node oppositeEdgeStartCandidate ) { } private boolean previousEdgeIntersectsInFrontOfOppositeEdge ( Node oppositeEdgeStartCandidate ) { } private boolean intersectionIsBehindReflexNode ( Node anotherRay ) { } private boolean isPointInAreaBetweenEdgeAndItsBisectors ( Point2D point ) { } private static boolean isPointNonConvex ( Point2D previous , Point2D point , Point2D next ) { } void eliminate2NodeLav ( Node neighbor ) { } }

Fix:
if ( ( ++ ( i ) ) > 1000 ) {